Acidification

By adding sulfuric acid to water, calcium bicarbonate is converted to calcium sulfate, minimizing scaling by the less soluble calcium carbonate. The reaction may be represented as follows:

Carbon dioxide formed is removed by aeration. Care must be exercised in adding acid to avoid corrosive conditions. With waters already high in sulfate, the solubility product of calcium sulfate may be exceeded, and unwanted precipitation is likely to occur.